Henry Miller, 19, collapsed after downing the herbal potion known as yaje with three other tourists.

Tribesmen tried in vain to revive Henry with nettle juice but he died on the way to hospital.

His body was found dumped by a roadside near the town of Mocoa in southern Colombia, close to the border with Ecuador.

Yaje is a widely-used by tribal people. It is said to bring on visions after severe vomiting and diarrhoea.

But a Colombian source said: “If you get a bad shaman or it’s not prepared right, it can go wrong.”

Colombian doctors are examining the body and the Foreign Office said it was assisting Henry’s family.

As reported by Mail Online, Mr Miller, from Bristol, was due to go to university in September.

He had been travelling round South America for a number of months and had recently arrived in Mocoa.

It is believed the teenager took the drug - which reportedly causes spiritual experiences - twice but collapsed on the second occasion.

Speaking to local reporters in Colombia, a source said at least a couple of people die each year from the drug. "Henry was a very decent polite young man who looked more like a student than a hippy," he said. "He was not the sort of person you would expect that would take Yage.

"I can't say very much as there is a police investigation."

It is believed Mr Miller was travelling alone but had met other travellers from around the world on his journey.